The eruption of Pavlof Volcano continues. Elevated seismic activity persists and a steam and ash cloud are visible in web camera images rising occasionally up to about 20,000 ft. above sea level. A diffuse ash plume was reported late last night at an altitude of 15,000 above sea level and extending downwind to the northeast for up to 100 miles before dissipating. A recent pilot report today indicated a dark ash cloud extending east-northeast at an altitude of 20,000 above sea level. National Weather Service issued a Sigmet yesterday that remains active today.

Residents of Cold Bay, located 37 miles southwest of the volcano, observed incandescent glow at the summit during the night. Pilot reports and photographs from yesterday afternoon indicate that the lava flow extending down the northwest flank is still active and has generated debris-laden flow deposits, presumably from interaction of hot lava with the snow and ice on the flank.

Elevated surface temperatures continued at Cleveland Volcano over the past 24 hours. No explosions have been detected by regional infrasound data. There has been no further information about the lava flow.

Sudden explosions of blocks and ash are possible with little or no warning. Ash clouds, if produced, could exceed 20,000 feet above sea level. If a large ash-producing event occurs, nearby seismic, infrasound, or volcanic lightning networks should alert AVO staff quickly. However, for some events, a delay of several hours is possible. Cleveland Volcano does not have a local seismic network and is monitored using only distant seismic and infrasound instruments and satellite data.

AVO will continue to monitor these volcanoes and issue additional information as available.

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

VOLCANO ALERT LEVELS

NORMALVolcano is in typical background, noneruptive state or, after a change from a higher level, volcanic activity has ceased and volcano has returned to noneruptive background state.

ADVISORYVolcano is exhibiting signs of elevated unrest above known background level or, after a change from a higher level, volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.

WATCHVolcano is exhibiting heightened or escalating unrest with increased potential of eruption, timeframe uncertain, OR eruption is underway but poses limited hazards.

WARNINGHazardous eruption is imminent, underway, or suspected.

AVIATION COLOR CODES

GREENVolcano is in typical background, noneruptive state or, after a change from a higher level, volcanic activity has ceased and volcano has returned to noneruptive background state.

YELLOWVolcano is exhibiting signs of elevated unrest above known background level or, after a change from a higher level, volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.

ORANGEVolcano is exhibiting heightened or escalating unrest with increased potential of eruption, timeframe uncertain, OR eruption is underway with no or minor volcanic-ash emissions [ash-plume height specified, if possible].

REDEruption is imminent with significant emission of volcanic ash into the atmosphere likely OR eruption is underway or suspected with significant emission of volcanic ash into the atmosphere [ash-plume height specified, if possible].